The present invention relates to a culture cell which is used in combination with a culture plate.
Hitherto a culture device shown in a schematic typical cross-sectional view of FIG. 11 which comprises plural culture wells 4 arranged on a culture plate 5 and culture cells 6 having membrane filters 2 has been used for studies on intercellular interaction, metabolism of cells and the like for the reasons that the studies on intercellular interactions of different kinds of cells can be carried out not only without contacts thereof but also under an in vitro system which is closely akin to the in vivo system.
However, such a culture device has several disadvantages. For example, cells to be cultured are injured by legs 8 of the culture cell 6 because the culture cell 6 is not fixed, and therefore, good reproducibility is hard to obtain. Furthermore, excess cells to be cultured are adhered to the legs 8, and therefore, a uniform cultivation cannot be achieved.
More recently, a culture cell shown in a schematic corss-sectional view of FIG. 12 is commercially available as "Transwell" (Costar Co., United States of America, Massachusetts, Cambridge) in order to solve these disadvantages. The culture cell 6 has a projecting part 1 for hanging the culture cell which is provided over the whole upper circumferential part, openings 7 for exchanging gas and for pipetting sample which are bored in the sidewall and membrane filter 2 which is provided on the bottom.
However, this improved culture cell has several disadvantages. For example, the gases are not exchanged sufficiently because the area of the openings 7 is small. Futhermore, culture capacity is restricted and culture liquid in inside and outside portions of the culture cell is apt to contaminate because the openings 7 are provided in the sidewall of the culture cell.
The present inventors have previously offered a culture cell 6 shown in FIG. 13 and FIG. 14 which comprises discontinuous projecting parts 1 for hanging the culture cell 6 provided on an upper circumferential part and a membrane filter 2 provided on a bottom, said culture cell having none of the aforesaid problems (Japanese Utility Model Application No. 77503/1987).
Although it is possible to pipet sample through a space between the culture cell 6 and the culture well 4 and to pour a culture medium for an exchange and the like into the space through the openings 7 without detaching the culture cell 6 from culture plate 5, the culture cell has a problem in that the diameter of the culture cell must be diminished in order to insert the tip of a micropipet into the openings 7, and therefore, an inside capacity of the culture cell and an effective area of the membrane filter are reduced and efficiencies of operation, cultivation and the like are decreased.
The object of the present invention is to provide an improved culture cell having none of the aforementioned problems.